Background
The bacterium now named Arcanobacterium haemolyticum was first described in 1946 as the pathogenic agent causing pharyngitis and cutaneous infections among US service members and indigenous peoples of the South Pacific.
As a result of its close resemblance to Corynebacterium pyogenes, some investigators believed the bacterium to be a mutant of this species and appended a subspecies name, C pyogenes subsp hominis.
Based on its peptidoglycan, fatty acid, and DNA characteristics, the bacterium was renamed and reclassified as the first member of the genus Arcanobacterium, which means “secretive bacteria.
” Since its original description, the spectrum of diseases caused by A haemolyticum has been expanded to include invasive infections, including sepsis and osteomyelitis. The importance of A haemolyticum to dermatology lies in the characteristic rash associated with pharyngeal infection. Interestingly, the cutaneous manifestations of A haemolyticum infection apparently were not reported in the dermatologic literature until 1996.
Also see Bacterial Pharyngitis.